Catchment area 30.7km2, length 20.4km. Not designated artificial or heavily modified.


Waterbody description

This section of the river flows on from Perrots Brook through Baunton alongside the A435 road and through Cirencester town centre. After Cirencester, the river continues through the village of Siddington and farmland to South Cerney. It is frequently split to create mill-leat channels for historic watermill uses. It flows past small privately-owned fishing lakes and through the South Cerney outdoor recreation areas. After flowing through the village of Cerney Wick the river splits into two channels, the more northerly channel being created to supply various old mill buildings. it then re-converges before skirting Cricklade and joining the Thames.

North of Siddington the river flows mainly over gravel substrate but there are some silty stretches where signal crayfish are causing bank erosion. It is subject to a wide fluctuation in water levels. Through Siddington it has a more natural meandering form with obvious areas of eroding banks. There is evidence of historic modification including channel enlargement and embanking in the water body, mill and flood meadow infrastructure. It has also been subjected to channel straightening throughout the South Cerney and Cricklade parishes. The modifications have reduced the biodiversity value of the river.

The River Churn has previously failed to reach good ecological status due to inadequate numbers and/or diversity of fish. Reasons include insufficient water levels and flows during the summer, over-predation by signal crayfish, physical modifications of the river creating barriers to fish movements, urbanisation destroying habitat and land drainage/agricultural activities. In 2016 it reached a good status for fish and moderate for macrophytes and phytobenthos.


Land use and designations

Land use in the catchment includes semi-improved pasture for grazing, woodland, historic water management systems, residential, recreational and commercial business and aggregate extraction. The area is crossed by various footpaths, the Sustrans 45 cycleway, and the Thames & Severn Way canal. Stakeholders include Bathurst Estate, Cotswold Flyfishers (CFF), the Welcome Trust, and Cricklade Town Council. The North Meadow National Nature Reserve, managed by Natural England and the Cricklade Court Leet is a part of the North Meadow and Clattinger Farm Special Area of Conservation and is designated for its very important lowland haymeadow plant community (including the nationally important population of Snakeshead Fritillary). There is no bank-side fencing on the Nature Reserve (the Commonland status means it cannot be permanently fenced) and there is damage of the river banks and bed by cattle accessing the watercourse from the opposite side. There are also areas of over-shading which prevents the sunlight from reaching the water and water’s edge inhibiting marginal and aquatic plant growth.


Flora from preliminary assessment

On sections that are fenced, there are dense stands of Reed Sweet-grass, Canary grass and rushes. Typical wetlands plants found such as Fool’s water Cress and Lesser water-parsnip, Floating sweet grass and Amphibious bistort, Fools Water Cress, Water mint and Lesser water-parsnip.

There are several large old Willow/Ash trees which have significant landscape and biodiversity value and native Black Poplar, a rare British tree included in the Cotswold Water Park Local Biodiversity Action Plan 2007-16 and currently the focus of a Gloucestershire FWAG tree planting project. Wildmoor way Meadows SSSI has unimproved grassland dominated by Crested Dogs tail, Common Knapweed and a healthy display of Southern Marsh Orchid.

Himalayan balsam is a major problem through South Cerney and Cricklade with a stronghold due to interconnected drains and ditches between the river and the disused Thames & Severn canal.


Signal crayfish are undermining the bank in places. Aquatic invertebrate life includes Beautiful damoiselle and Keeled Skimmer. Fish species are known to include Chub, Dace, Roach, Brown Trout (some natural and some stocked), Brook lamprey, Minnow, Bullhead and occasional Perch and Pike.

Signs of Otter were recorded along this stretch of the river. A survey by Cotswold Water Park Trust in Autumn 2014 found Water Vole were present in low numbers. Kingfisher and Grey Wagtail were also recorded (Amber Listed species) and Song Thrush, Spotted Flycatcher and Yellowhammer (Red Listed species).


Main conclusions from the WILD parish reports 1

Overall the Churn through Siddington parish is of high ecological value, particularly where the river has been fenced from livestock with a wide buffer. The river appears to have reasonable quality water due to the presence of indicator species such as Dipper. All sections have a high ecological potential that could be achieved by enhancements to riparian management some of which are already being implemented by the river tenants and the landowners. Through South Cerney and Cricklade parishes it is of significant ecological value, despite the modifications and the impact of some land uses and associated infrastructure, trees, and scrub. Through Cricklade, its main value to fish is during the winter when it has significant flow and it can act as a bypass channel. During the summer it generally is too dry, silty and lacking in aquatic vegetation to have much value for all but the smaller fish species, but it does have value for Water Vole.


Catchment Issues

Land to the south of Siddington is subject to flooding during high rainfall periods. There is also a relatively high risk of flooding throughout South Cerney and Cricklade parishes with most of the land being in the natural floodplain, however, the village/town are at low risk. North Meadow has always flooded throughout history and Natural England has improved the connectivity of the floodplain to the river.

This catchment has a strong presence of invasive species; Signal crayfish and Himalayan balsam.

  1. WILD Project, River Churn Management Plan, South Cerney Parish (June 2015), Siddington Parish (April 2015), Ashton Keynes Parish (March 2016)


Water Framework Directive

WFD 2016 achieved a Moderate overall status with the Fish element ‘Good’ after being consistently bad or poor previously. Macrophytes and phytobenthos were assessed as Moderate.


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